<!DOCTYPE html>
<html lang="cn">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style type="text/css">
        header{
            width: 100%;
            height: 100px;
            background-color: #369;
            color:#fff;
            display: block;
        }
        nav{
            width: 80%;
            height: 50px;
            margin: 0 auto;
            margin-top: 20px;
            background-color: #ccc;
        }
        div{
            width: 100%;
            height: 450px;
            background-color: #f90;
        }
        footer{
            width: 100%;
            height: 80px;
            background-color: #666;
        }
    </style>
    <script>
        // document.createElement('header');
    </script>
    <script src="./html5shiv.min.js"></script>
</head>
<body>
    <h1>兼容不支持HTML5标签的浏览器</h1>
    <hr>

    <header>
        我来组成头部
        <nav></nav>
    </header>

    <div>
        我来组成身体
    </div>

    <footer>我来组成臭脚</footer>


    
</body>
</html>




